Cummins ISBe CM800- Probelm

[mathura]

The engine is mounted in a DAF Truck, ISBe CM 800
The engine is hard starting most times but sometimes(rarely) it will start quick.
There are no active codes present. One amazing thing is that after the key is turned off the fuel actuator solenoid remains energised for about 2 to 3 minutes. You can hear the actuator humming with the engine stopped.

After key off the actuator was disconnected and test showed that 5.5V was still present at the terminals for 2 minutes.

First time I am attending to this job but I was told by owner that he replaced high pressure pump six months ago and the engine was starting fine until recently he developed the hard starting, and noticed the humming after key off.

Thanks for your suggestions on this probelm.

[jctech]

The engine is mounted in a DAF Truck, ISBe CM 800
The engine is hard starting most times but sometimes(rarely) it will start quick.
There are no active codes present. One amazing thing is that after the key is turned off the fuel actuator solenoid remains energised for about 2 to 3 minutes. You can hear the actuator humming with the engine stopped.

After key off the actuator was disconnected and test showed that 5.5V was still present at the terminals for 2 minutes.

First time I am attending to this job but I was told by owner that he replaced high pressure pump six months ago and the engine was starting fine until recently he developed the hard starting, and noticed the humming after key off.

Thanks for your suggestions on this probelm.

A very common problem with this engine is excessive fuel leakage through the injectors. The symptom is hard to start when hot and eventually hard to start and then no start.
This shows up as a high return fuel flow from the rear of the cylinder head.
Carry out the injector leakage test as described in the T&R manual.

[mathura]

A very common problem with this engine is excessive fuel leakage through the injectors. The symptom is hard to start when hot and eventually hard to start and then no start.
This shows up as a high return fuel flow from the rear of the cylinder head.
Carry out the injector leakage test as described in the T&R manual.

Thanks for the response

Any ideas why the fuel actuator remains energised after the ignition is switched off.

[hercamp]

how jc say ..injectors if all is ok and pessure ok ......all timmme is the ecm ......check arnnes and other ecm ...u will find answer fast.

[mathura]

how jc say ..injectors if all is ok and pessure ok ......all timmme is the ecm ......check arnnes and other ecm ...u will find answer fast.

Thanks
Harness tested ok
The reason for the energised fuel actuator after key off is my concern but I do not have another ECM to try at this time.

Also let me mention that communication to ecm with insite is disturbed many times while monitoring the engine. The engine RPM also is not stable it surges at times while idling.

[jctech]

It could be an ECM or power supply problem, but just because it is an electronic engine does not mean that your problem is electronic, it could just as easy be a fuel issue.

[patricio65]

Hi guys, anybody can help me with ecm 800 in ISBe engine?
I need to rom boot the module, anybody have wiring or procedure to do it?
Thanksssssssssssss

[ddmech]

Calterm is easiest if you have it.Posted on dk if you need it.

[mathura]

This is for another Truck DAF with ISBe 6 cylinder.

The probelm is that while driving you get a flat spot (loss of acceleration) for a few seconds and then works normal again, this happens like once or twice every 5 minutes. Sometimes it does not happens for hours and driving is normal.

I have checked the entire fuel system but came up with nothing. I even tried another wiring harness.

Any help will be appreciated

Thanks

[Poptest]

Remove fuel actuator from high pressure pump and clean it. Or borrow fuel actuator from a good engine to verify condition of original actuator.

[mathura]

Remove fuel actuator from high pressure pump and clean it. Or borrow fuel actuator from a good engine to verify condition of original actuator.

Hi Poptest
That was my thinking so I installed another actuator but the same probelm exists, I even tried another rail pressure sensor.

[Poptest]

Hi Poptest
That was my thinking so I installed another actuator but the same probelm exists, I even tried another rail pressure sensor.

Check connector socket to the actuator.....sometimes, the socket is loose.

Also check for air ingress from suction side.

No fault codes?

Good luck my friend....

[mathura]

Check connector socket to the actuator.....sometimes, the socket is loose.

Also check for air ingress from suction side.

No fault codes?

Good luck my friend....


I have checked those area already and came up with nothing, still looking for other suggestions.

Other members here must have worked with these engines, hope they can come up with some ideas

Thanks

[alsop]

I have checked those area already and came up with nothing, still looking for other suggestions.

Other members here must have worked with these engines, hope they can come up with some ideas

ThanksTry going after the TPS. I've seen where they plug into the harness with weatherpack connectors the operators can hit them with their feet and cause a momentary bad connection and not cause a code. Or a defective one has a bad spot that won't respond then picks back up and still not log a code. Just a thought and easy to check.

[mathura]

Try going after the TPS. I've seen where they plug into the harness with weatherpack connectors the operators can hit them with their feet and cause a momentary bad connection and not cause a code. Or a defective one has a bad spot that won't respond then picks back up and still not log a code. Just a thought and easy to check.

I replaced TPS sensor and plug but no improvement

[alsop]

Back to fuel or exhaust back pressure. TPS was worth a try. The actuator running is also a mystery problem. Jctech is normally spot on when it comes to problems like this.

[mathura]

Back to fuel or exhaust back pressure. TPS was worth a try. The actuator running is also a mystery problem. Jctech is normally spot on when it comes to problems like this.

Yes I know its something to do with fuel system but simply not getting it right, and of course I agree that JCtech is spot on with these issues.

[pbateman]

Mathura look at the ECM casing and make sure there are no dents in it. I ran into an issue something similar on a pete that had an engine pulled and when they pulled the engine they left the ECM on and it had just a ding in it the size of pen tip and it was just in the right spot of the ECM where the TPS part of the board was hit but not throwing a fault code. So I finally swapped ECM's and it cure my issue

[mang5087]

This is for another Truck DAF with ISBe 6 cylinder.

The probelm is that while driving you get a flat spot (loss of acceleration) for a few seconds and then works normal again, this happens like once or twice every 5 minutes. Sometimes it does not happens for hours and driving is normal.

I have checked the entire fuel system but came up with nothing. I even tried another wiring harness.

Any help will be appreciated

Thanks

try Data Monitor/Logger & record look for
parameters not in specs. thanks

[mathura]

OK I have had another look today and its now throwing a code 2215 -
Fuel Rail Pressure Positive Deviation Error. Fuel rail pressure signal indicates that fuel pressure is consistently lower than the commanded fuel pressure.

However the code is inactive but has a high count of 255 times. I cleared the code and had the engine monitored for 30 minutes, at varying engine speed but nothing unusual.
Road tested for 2 miles and came back with the 2215 code inactive, 5 times. The driver confirmed that he felt the loss in acceleration about 8 times.

[mang5087]

have you checked inj line tube nuts
for proper tq? this can cause lower
fuel press than commanded. thanks

[dimitar22]

OK I have had another look today and its now throwing a code 2215 -
Fuel Rail Pressure Positive Deviation Error. Fuel rail pressure signal indicates that fuel pressure is consistently lower than the commanded fuel pressure.

However the code is inactive but has a high count of 255 times. I cleared the code and had the engine monitored for 30 minutes, at varying engine speed but nothing unusual.
Road tested for 2 miles and came back with the 2215 code inactive, 5 times. The driver confirmed that he felt the loss in acceleration about 8 times.

Check the injectors.
Maybe the injectors have too great leakage at return line.
Had problems like this on MAN D20 common rail

[mathura]

have you checked inj line tube nuts
for proper tq? this can cause lower
fuel press than commanded. thanks

I have looked at the leak off from the head and that is ok. I have been monitoring the pressures with insite while the engine is idling and I was lucky to see a stumble of the engine but what I noticed is that the pressures measured was ok but the EFC actuator duty cycle down to 0% for a split second, when the stumble occoured.

[mang5087]

I have looked at the leak off from the head and that is ok. I have been monitoring the pressures with insite while the engine is idling and I was lucky to see a stumble of the engine but what I noticed is that the pressures measured was ok but the EFC actuator duty cycle down to 0% for a split second, when the stumble occoured.

ok, that means ecm is asking for
more fuel. the tube nuts will not
leak to outside, but can leak internal.
if they are loose any, they can cause
this problem. also check pressure relief
valve. hope this helps. thanks

[alsop]

This may sound stupid but I was viewing the CVC CD's and watched where an operator of a truck had changed the fuel caps to a key lock type causing improper venting and fuel delivery problems between the saddle tanks. I doubt it's the problem but worth a look at.

[mathura]

This may sound stupid but I was viewing the CVC CD's and watched where an operator of a truck had changed the fuel caps to a key lock type causing improper venting and fuel delivery problems between the saddle tanks. I doubt it's the problem but worth a look at.

Every suggestion is good at this time nothing is stupid because the probelm is still there unsolved

[Poptest]

I have looked at the leak off from the head and that is ok. I have been monitoring the pressures with insite while the engine is idling and I was lucky to see a stumble of the engine but what I noticed is that the pressures measured was ok but the EFC actuator duty cycle down to 0% for a split second, when the stumble occoured.

This engine's EFC is ETSO (energize to shut-off). Engine should briefly rev up if EFC has a momentary loss of current, or if duty cycle drops to 0% as the EFC will admit more fuel to the high pressure pump. However, the engine is doing the opposite.

Check the pressure relief valve on the rail for intermittent leakage. ECM could be pushing the pump to deliver more pressure by dropping duty cycle current to EFC.

Check for intermittent air ingress.

Check for temporary loss of battery voltage through ignition switch.

These are just my thoughts, and I hope it helps.

[Poptest]

Attached is Cummins TSB on improved rail pressure sensor which may cure other faults including 2215.

[pbateman]

Hey mathura here is something else to check I had just remembered. We have run into this on several trucks and it's an issue you can see. Try unhooking main fuel line and running it into a clean bucket of fuel. If it runs ok then your issue is in the fuel tank or a possible colasping fuel line but I would almost be willing to bet your gonna find the issue we have found and that is there is a crack in the suction line somewhere at the inside near the top of the tank. Other ways to tell is if the fuel tank isn't full fill it up and see how it runs and run the tank down. But by what you are describing we have had several issues like this also and it was the fuel tanks. Plus one more thing I can think of fuel wise that I have run into that will not always show is the fuel pump or the spider gear can crack in half. Hope this help with some other areas to look at.

[mathura]

Thank you so much Pbateman, I think you came up with some good suggestions, I will try these as soon as I have the truck back.

[mathura]

This engine's EFC is ETSO (energize to shut-off). Engine should briefly rev up if EFC has a momentary loss of current, or if duty cycle drops to 0% as the EFC will admit more fuel to the high pressure pump. However, the engine is doing the opposite.

Check the pressure relief valve on the rail for intermittent leakage. ECM could be pushing the pump to deliver more pressure by dropping duty cycle current to EFC.

Check for intermittent air ingress.

Check for temporary loss of battery voltage through ignition switch.

These are just my thoughts, and I hope it helps.

I think that is what is happening, the engine is really revving up for a split second but I probably describe it as a stumble because after the revving up it goes back down and seems to be cutting out. This happens like less than half of a second when monitored on the graph with insite data monitor logger.

[Poptest]

I think that is what is happening, the engine is really revving up for a split second but I probably describe it as a stumble because after the revving up it goes back down and seems to be cutting out. This happens like less than half of a second when monitored on the graph with insite data monitor logger.

The ecm may be detecting a momentary drop in rail pressure and is pushing the CR pump to deliver more flow. I would do the following:


Do a wiggle test on the rail pressure sensor harness and connector. Sensor pins may have a loose fit on the connector/s.
Use an analog meter to measure rail pressure supply and feedback voltages at the sensor and at the ECM side. Insite may not be able to rapidly display a drop in rail pressure. An analog meter will react faster than Insite or a DMM.
If brief voltage fluctuation is detected on the RPS, further evaluation will have to be done to determine if this is a true pressure drop or if this is due to a faulty sensor or harness.

Good luck Mathura.....

[markpollard4]

tighten the fuel tube nuts. this brings up 2215 all the time. this is a common fault. when you undo the injector pipes, shine a torch on the fuel tube and see if it turns a bit with the injector pipe. im sure this will not show up on leakage test from back of head.